<template>
  <div style='padding: 10px; margin-bottom: 50px'>
    <el-row>
      <el-col :span='4'>
        <el-card style='width: 300px; height: 300px; color: #333'>
          <div style='padding-bottom: 10px; border-bottom: 1px solid #ccc'>在线用户<span
              style='font-size: 12px'>（点击聊天气泡开始聊天）</span></div>
          <div style='padding: 10px 0' v-for='user in users' :key='user.username'>
            <span>{{ user.username }}</span>
            <i class='el-icon-chat-dot-round' style='margin-left: 10px; font-size: 16px; cursor: pointer'
               @click='chonseUser(user.username)'></i>
            <!--               @click="chatUser = user.username"></i>-->

            <span style='font-size: 12px;color: limegreen; margin-left: 5px'
                  v-if='user.username === chatUser'>chatting...</span>
          </div>
        </el-card>
      </el-col>
      <el-col :span='20'>
        <div style='width: 800px; margin: 0 auto; background-color: white;
                    border-radius: 5px; box-shadow: 0 0 10px #ccc'>
          <div style='text-align: center; line-height: 50px;'>
            Web聊天室（{{ chatUser }}）
          </div>
          <div style='height: 350px; overflow:auto; border-top: 1px solid #ccc' v-html='content'></div>
          <div style='height: 200px'>
            <textarea v-model='text' style='height: 160px; width: 740px; padding: 20px; border: none; border-top: 1px solid #ccc;
             border-bottom: 1px solid #ccc; outline: none'></textarea>
            <div style='text-align: right; padding-right: 10px'>
              <el-button type='primary' size='mini' @click='send'>发送</el-button>
            </div>
          </div>
        </div>
      </el-col>
    </el-row>
  </div>
</template>
<script>

let socket;
export default {
  name: 'Im',
  data() {
    return {
      circleUrl: 'https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png',
      // 自己
      user: {},
      isCollapse: false,
      // 目标list
      users: [],
      // 选中的目标
      chatUser: '',
      text: '',
      messages: [],
      content: ''
    };
  },
  created() {
    this.init();
  },
  methods: {
    chonseUser(toUser){
      this.chatUser=toUser
      console.log("from->"+this.user+",to->"+toUser)
      this.$http.get("/chat/getChatRecords/"+this.user+"/"+toUser).then(resp=>{
        resp.data.data.forEach(e=>{
          this.createContent(e.tos,e.froms,e.msg)
        })
      })
    },
    send() {
      if (!this.chatUser) {
        this.$message({ type: 'warning', message: '请选择聊天对象' });
        return;
      }
      if (!this.text) {
        this.$message({ type: 'warning', message: '请输入内容' });
      } else {
        if (typeof (WebSocket) == 'undefined') {
          console.log('您的浏览器不支持WebSocket');
        } else {
          console.log('您的浏览器支持WebSocket');
          // 组装待发送的消息 json
          // {"from": "zhang", "to": "admin", "text": "聊天文本"}
          let message = { from: this.user.username, to: this.chatUser, text: this.text };
          socket.send(JSON.stringify(message));  // 将组装好的json发送给服务端，由服务端进行转发
          this.messages.push({ user: this.user, text: this.text });
          // 构建消息内容，本人消息
          this.createContent(null, this.user, this.text);
          this.text = '';
        }
      }
    },
    createContent(remoteUser, nowUser, text) {  // 这个方法是用来将 json的聊天消息数据转换成 html的。
      let html;
      // 当前用户消息
      if (nowUser==this.user) { // nowUser 表示是否显示当前用户发送的聊天消息，绿色气泡
        html = '<div class="el-row" style="padding: 5px 0">\n' +
            '  <div class="el-col el-col-22" style="text-align: right; padding-right: 10px">\n' +
            '    <div class="tip left">' + text + '</div>\n' +
            '  </div>\n' +
            '  <div class="el-col el-col-2">\n' +
            '  <span class="el-avatar el-avatar--circle" style="height: 40px; width: 40px; line-height: 40px;">\n' +
            '    <img src="https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png" style="object-fit: cover;">\n' +
            '  </span>\n' +
            '  </div>\n' +
            '</div>';
      } else  {   // remoteUser表示远程用户聊天消息，蓝色的气泡
        html = '<div class="el-row" style="padding: 5px 0">\n' +
            '  <div class="el-col el-col-2" style="text-align: right">\n' +
            '  <span class="el-avatar el-avatar--circle" style="height: 40px; width: 40px; line-height: 40px;">\n' +
            '    <img src="https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png" style="object-fit: cover;">\n' +
            '  </span>\n' +
            '  </div>\n' +
            '  <div class="el-col el-col-22" style="text-align: left; padding-left: 10px">\n' +
            '    <div class="tip right">' + text + '</div>\n' +
            '  </div>\n' +
            '</div>';
      }
      this.content += html;
    },
    init() {
      this.user = "Customer";
      console.log(this.user);
      let username = this.user;
      let _this = this;
      if (typeof (WebSocket) == 'undefined') {
        console.log('您的浏览器不支持WebSocket');
      } else {
        console.log('您的浏览器支持WebSocket');
        let socketUrl = 'ws://localhost:8081/chatserver/' + username;
        if (socket != null) {
          socket.close();
          socket = null;
        }
        // 开启一个websocket服务
        socket = new WebSocket(socketUrl);
        //打开事件
        socket.onopen = function() {
          console.log('websocket已打开');
        };
        //  浏览器端收消息，获得从服务端发送过来的文本消息
        socket.onmessage = function(msg) {
          console.log('收到数据====' + msg.data);
          let data = JSON.parse(msg.data);  // 对收到的json数据进行解析， 类似这样的： {"users": [{"username": "zhang"},{ "username": "admin"}]}
          if (data.users) {  // 获取在线人员信息
            _this.users = data.users.filter(user => user.username !== username);  // 获取当前连接的所有用户信息，并且排除自身，自己不会出现在自己的聊天列表里
          } else {
            // 如果服务器端发送过来的json数据 不包含 users 这个key，那么发送过来的就是聊天文本json数据
            //  // {"from": "zhang", "text": "hello"}
            _this.chatUser = data.from;
            // if (data.from === _this.chatUser) {
            _this.messages.push(data);
            // 构建消息内容
            _this.createContent(data.from, null, data.text);
          }
          // }
        };
        //关闭事件
        socket.onclose = function() {
          console.log('websocket已关闭');
        };
        //发生了错误事件
        socket.onerror = function() {
          console.log('websocket发生了错误');
        };
      }
    }
  }
};
</script>
<style>
.tip {
  color: white;
  text-align: center;
  border-radius: 10px;
  font-family: sans-serif;
  padding: 10px;
  width: auto;
  display: inline-block !important;
  display: inline;
}

.right {
  background-color: deepskyblue;
}

.left {
  background-color: forestgreen;
}
</style>
